cut：截取文本特定字段

NAME
       cut - remove sections from each line of files

-d, --delimiter=DELIM（指定字段分隔符，默认是空格）

              use DELIM instead of TAB for field delimiter

-f, --fields=LIST（指定要显示的字段）

              select  only  these  fields;  also print any line that contains no delimiter character,
              unless the -s option is specified
  -f 1,3
  -f 1-3

[rhel@localhost ~]$ cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown

[rhel@localhost ~]$ cut -d : -f1 /etc/passwd
root
bin
daemon
adm
lp
sync
shutdown

sort：文本排序，以ascii

NAME
       sort - sort lines of text files

SYNOPSIS
       sort [OPTION]... [FILE]...
       sort [OPTION]... --files0-from=F

[rhel@localhost ~]$ cat sort.txt
3
5
1
4
9
[rhel@localhost ~]$ sort sort.txt
1
3
4
5
9
[rhel@localhost ~]$

-n, --numeric-sort（数值排序）
              compare according to string numerical value

-r, --reverse（反向排序）
              reverse the result of comparisons

[rhel@localhost ~]$ sort -r sort.txt
9
5
4
3
1
[rhel@localhost ~]$

-t, --field-separator=SEP（字段分隔符）
              use SEP instead of non-blank to blank transition

-k, --key=POS1[,POS2]（关键字进行排序）

              start a key at POS1 (origin 1), end it at POS2 (default end of line)

[rhel@localhost ~]$ sort -t: -k3 -n  /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin

-u, --unique（删除重复项）
              with -c, check for strict ordering; without -c, output only the first of an equal run

[rhel@localhost ~]$ cat sort.txt
3
5
1
4
43
9
4
11
[rhel@localhost ~]$ sort -u sort.txt
1
11
3
4
43
5
9

uniq：显示或者忽略重复行

NAME
       uniq - report or omit repeated lines

-d, --repeated（只显示重复行）
              only print duplicate lines

[rhel@localhost ~]$ uniq sort.txt
3
5
1
4
43
9
4
11
[rhel@localhost ~]$ uniq -d sort.txt
3
1
[rhel@localhost ~]$

-D, --all-repeated[=delimit-method]（显示所有重复）
              print all duplicate lines delimit-method={none(default),prepend,separate} Delimiting is
              done with blank lines.

[rhel@localhost ~]$ uniq -D sort.txt
3
3
1
1
[rhel@localhost ~]$

-c, --count（显示文件行重复的次数）
              prefix lines by the number of occurrences

[rhel@localhost ~]$ uniq -c sort.txt
      2 3
      1 5
      2 1
      1 4
      1 43
      1 9
      1 4
      1 11
[rhel@localhost ~]$

wc：显示文件中行数/单词数/字节数

NAME
       wc - print newline, word, and byte counts for each file

SYNOPSIS
       wc [OPTION]... [FILE]...
       wc [OPTION]... --files0-from=F

-l, --lines
              print the newline counts

[rhel@localhost ~]$ wc /etc/fstab
 15  78 805 /etc/fstab
[rhel@localhost ~]$ man wc
[rhel@localhost ~]$ wc -l /etc/fstab
15 /etc/fstab

-w, --words
              print the word counts

[rhel@localhost ~]$ wc /etc/fstab
 15  78 805 /etc/fstab

[rhel@localhost ~]$ wc -w /etc/fstab
78 /etc/fstab
[rhel@localhost ~]$

-c, --bytes
              print the byte counts

[rhel@localhost ~]$ wc /etc/fstab
 15  78 805 /etc/fstab

[rhel@localhost ~]$ wc -c /etc/fstab
805 /etc/fstab

-L, --max-line-length（最长行字符数）
              print the length of the longest line

[rhel@localhost ~]$ wc -L /etc/fstab
93 /etc/fstab

tr：转换或者删除字符

NAME
       tr - translate or delete characters

SYNOPSIS
       tr [OPTION]... SET1 [SET2]

[rhel@localhost ~]$ tr ‘ab‘ ‘AB‘
abc
ABc
able
ABle
again
AgAin
^C
[rhel@localhost ~]$

[rhel@localhost ~]$ tr ‘a-z‘ ‘A-Z‘ < /etc/passwd
ROOT:X:0:0:ROOT:/ROOT:/BIN/BASH
BIN:X:1:1:BIN:/BIN:/SBIN/NOLOGIN
DAEMON:X:2:2:DAEMON:/SBIN:/SBIN/NOLOGIN
ADM:X:3:4:ADM:/VAR/ADM:/SBIN/NOLOGIN
LP:X:4:7:LP:/VAR/SPOOL/LPD:/SBIN/NOLOGIN
SYNC:X:5:0:SYNC:/SBIN:/BIN/SYNC
SHUTDOWN:X:6:0:SHUTDOWN:/SBIN:/SBIN/SHUTDOWN

-d, --delete（删除字符集）
              delete characters in SET1, do not translate

[rhel@localhost ~]$ tr -d ‘ab‘
alb^H^H^[[3~^[[3~
‘
‘
able
le
a

enable
enle

linux常用命令-文本处理cut,sort,uniq,wc,tr